Just out south of Dannevirke is a dairy farm with a composting shelter that can fit the farm’s entire 650-cow herd inside.
But it doesn’t smell much of manure, if at all, as tiny micro-organisms then work to turn the poo into compost for fertiliser.
Waka Dairies hasbeen on a journey of discovery since Aztech Buildings constructed the composting shelter for its cows seven years ago.
The herd generates enough milk to feed 38,000 people’s daily dairy intake every day.
All things going to plan, aerobic digestion in the shed breaks down the herd’s manure and generates heat to dry the carbon bedding that the cows live on.
Waka Dairies managing director Michael Phillips said despite the whole system relying on the use of cow poo, the shed was odourless due to the composting properties.
The precision dairy farm has five focus areas it wants to hit - food, energy, natural capital, skills and culture - to accomplish its aim of being a leading producer.
Part of its goal for natural capital was to reduce spending on synthetic fertilisers and reduce leaching.
“We are on our journey of learning and understanding how to operate it at a technical level.”
Phillips said the clean and dry shelter had a roof over the area with a floor layered with carbon in the form of sawdust or woodchips with enough space to fit the entire herd.
The shelter is used for 80% of the year and the cattle could spend anywhere from 20 hours a day for weeks at a time over winter to a couple of hours for heat stress release.
“We put our cows on that at different times of the year and we decide that based on environmental conditions.”
The cows are able to move freely and generally graze outside or on the feed pad, with the option of “top up” feed provided in the shelter.
“They generally just like to sit and relax,” Phillips said.
The decision to put the cows inside was based on the weather, and whether it was too hot and dry or too wet and cold outside for the cows.
Phillips said the activity from the micro-organisms created a temperature of around 45C to 55C, which helped to keep the composting floor space sanitary.
“We aerate it every day, we rip with our tractor and rippers to get air into the bedding pack and when we rip it, it steams and lets moisture out”
A test is carried out three days a week to understand and monitor the temperature and moisture content.
“We have got our bed of carbon, and the nitrogen is added by the cows and when that gets to a certain point the microbiology is right for the composting process to occur.”
Phillips said the compost was eventually applied to cropping grounds as fertiliser which helped improve soil health.
“We are using an organic byproduct of a material that we produce on the farm and apply that to the ground.
“What we find is there is a lot more organic matter in the soil structure so there is a lot more ability for moisture retention to occur and healthy plants.”
He said this led to better quality and volume of feed for the cattle which generated better yield.
The benefits could also be seen in the “environmental impacts that we don’t have because of that system”, Phillips said.
“We are not leaching anywhere near as many nitrates or minerals because we have the ability to have our animals off the ground during the high leaching periods like winter.”
The compost can be stored and applied at the optimum time for ground conditions.
“You don’t really see it flow through into a change of composition of the milk but it’s about the story behind those other pieces.”
Phillips said producing quality milk is an essential goal and Waka Dairies has found a great way to utilise the cattle byproduct and redistribute it on the family farm.
“We try to feed the world.”
Phillips hoped by 2050 they would be producing and consuming their own energy through the use of solar, wind, micro-hydro, and biogas on the farm.
Michaela Gower joined Hawke’s Bay Today in 2023 and is based out of the Hastings and Central Hawke’s Bay newsrooms. She covers Dannevirke and Hawke’s Bay news and has a love for sharing stories about farming and rural communities.